Aggregation and Emergence in Agent-Based Models: A Markov Chain Approach

We analyze the dynamics of agent--based models (ABMs) from a Markovian perspective and derive explicit statements about the possibility of linking a microscopic agent model to the dynamical processes of macroscopic observables that are useful for a precise understanding of the model dynamics. In this way the dynamics of collective variables may be studied, and a description of macro dynamics as emergent properties of micro dynamics, in particular during transient times, is possible.Comment: 5 pages, 1 figur

Causality and Cointegration in Stock Markets: The Case of Latin America

This paper analyzes causality and cointegration relationships among stock markets for Latin America and the United States. Within a simple framework causality and cointegration is tested for Argentina, Brazil, Chile, Colombia, Mexico, Peru, Venezuela and the US. We found no evidence of cointegration among these stock markets but short-run causality could not be rejected. Furthermore, we use impulse response functions to analyze the relative impact of shocks in the US stock index (Dow Jones) on Latin American indexes. Evidence suggests that the responses differ significantly among these countries. These findings imply that there are valuable opportunities to international investors from diversifying in US and Latin American stocks.

The Effects of the Brazilian ADRs Program on Domestic Market Efficiency

This paper examines the impact on Brazilian stocks following American Depositary Receipts (ADRs) listing in the U.S. stock markets. Evidence suggests that a systematic change has taken place in the post-listing period as the multivariate variance ratio statistics have significantly decreased if compared to the pre-listing period, which indicates a move toward a more efficient domestic stock market. This empirical evidence is robust to the use of dollar and local currency-denominated returns. These results add to the literature that finds evidence on changes in domestic volatility and abnormal returns around listing dates.

Exchange Rate Dynamics and the Relationship between the Random Walk Hypothesis and Official Interventions

This paper examines the empirical evidence that official interventions are associated with periods of high predictability in exchange rate markets. We employ a block bootstrap methodology to build critical values for the Variance Ratio statistics and test for predictability within moving windows of fixed length sizes for major developed countries currencies. Empirical results suggest that interventions are indeed associated to periods of increase in predictability and that time varying risk premium may, at least partially, explain such results.

Building Confidence Intervals with Block Bootstraps for the Variance Ratio Test of Predictability

This paper compares different versions of the multiple variance ratio test based on bootstrap techniques for the construction of empirical distributions. It also analyzes the crucial issue of selecting optimal block sizes when block bootstrap procedures are used, by applying the methods developed by Hall et al. (1995) and by Politis and White (2004). By comparing the results of the different methods using Monte Carlo simulations, we conclude that methodologies using block bootstrap methods present better performance for the construction of empirical distributions of the variance ratio test. Moreover, the results are highly sensitive to methods employed to test the null hypothesis of random walk.

Multiespacialidades metropolitanas e construção social do lugar – rumos para a sustentabilidade

The metropolitan region of Curitiba – MRC – contains several spatial configurations and, besides having the third automobile industry of the country; it is currently the only metropolitan region with a population growth rate higher than the national average. Between 1970 and 2000, it had the highest geometric growth rate among metropolitan regions in Brazil: it grew 2.13% in its core and 4.18% in the suburbs(IBGE, 2000). However, last places are where 90% of the population live. There, social and urban structures are underdeveloped and the population number has risen three times in the last twenty years. Whereas in Curitiba 12.46% of the houses have an income around US $80 per month, in the suburbs this proportion rises to 50% or more. Discussing sustainability, it is necessary to understand the environmental dimension as a social and natural whole. In this paper analyze some aspects of the population conditions in the nearest neighborhood of Curitiba, where an improvement of the locus sense of place could contribute to a metropolitan and urban sustainability

Gênero e sexualidade na escola em tempos de globalização: perspectivas e culturas adolescentes no Pantanal de Mato Grosso do Sul

Masculinity and femininity, gender identity and sexualities expressed by juveniles nowadays, require scientific care and refinement for teacher formation, new cultures and latent social expressions debate. This discussion brings together researches and interdisciplinary approach, expanding epistemology and social dialogs on education, health and human rights. The proposal of knowing aspects and cultures of gender, sexuality and diversity, offers a triangulation of methods for qualitative research, descriptive designs on themes, considering the challenges of collecting data, participant observation and cross-sectional studies over juveniles’ representations. Scenario presents health and care observation of a high school in Pantanal of Mato Grosso do Sul and its repercussion in Undergraduate Course in Education. Results are presented when we debate school’s responsibility for mediating knowledge on these topics, while it indicates the need for appropriate formation over gender, sexuality and diversity.Las masculinidades e feminilidades, identidades de género y sexualidades expresadas por adolescentes hoy, demanda atención y refinamiento científico para formación de professores, en el debate sobre la nuevas culturas y expresiones sociales latentes. Viene la discussión acercando los estudiosos y áreas interdisciplinarias, ponendo las epistemologias en expansión y los diálogos sociales en las áreas de educación, salud y derechos humanos. La proposición de conocer aspectos de la cultura de género, sexualidade o diversidad, trae a nosotros una proposición de triangulación de métodos, para investigaciones qualitativas, dibujos exploratórios temáticos, considerando los desafios para la recompilación de datos, la observación participante y análises transversales acerca de las representaciones de los adolescentes. Se presenta experimento en educación y salud en una escuela secundaria en el Pantanal de Mato Grosso do Sul y sus reverberaciones en el grado de Pedagogía en la Universidad. Los resultados se presentan en momento que discutimos la necesidad de la escuela como mediadora del conocimiento en estas temáticas, asi como la necesaria formación de profesores en género, sexualidade e diversidad.As masculinidades e feminilidades, identidades de gênero e sexualidades expressas pelos adolescentes na atualidade, demandam atenção e refinamento científico para a formação de professores no debate sobre as novas culturas e expressões sociais latentes. Essa discussão vem aproximando pesquisadores e áreas interdisciplinares, ampliando as epistemologias e diálogos sociais nas áreas de educação, saúde e direitos humanos. A proposição de conhecer aspectos e culturas em gênero, sexualidade e diversidade, traz a triangulação de métodos para a pesquisa qualitativa, os desenhos exploratórios sobre as temáticas, considerando os desafios para coleta de dados, observação participante e análises transversais sobre as representações adolescentes. O pano de fundo apresenta um experimento em educação e saúde numa escola de ensino médio no Pantanal de Mato Grosso do Sul e suas reverberações na graduação em Pedagogia na Universidade. Os resultados se apresentam no momento em que discutimos a necessidade de a escola mediar o conhecimento acerca dessas temáticas, bem como a necessária formação docente em gênero, sexualidade e diversidade

Quando a máquina ataca: notas sobre cinema e engajamento

Este artigo busca pensar alguns modos de embate de que tem lançado mão o cinema para lidar com as problemáticas gestões do espaço urbano, em nosso presente histórico. De um lado, pensamos como a máquina-cinema se engaja no tempo histórico e nas experiências do mundo vivido para produzir um mundo imaginado. De outro, tentamos analisar as materialidades fílmicas, para indagar sobre as modalidades de afetação que elas podem traçar com o corpo do espectador. Essa articulação se dá junto às singularidades de dois filmes do cinema brasileiro recente, Nova Dubai (Gustavo Vinagre, 2014) e Branco sai preto fica (Adirley Queirós, 2014), que traçam dois caminhos distintos de engajamento, como tentaremos indicar. Interessa-nos pensar como esses trabalhos, cada um a seu modo, oferecem vias de articulação entre o real e as potências de atração do cinema, desdobrando diretos ataques políticos a configurações territoriais na cena urbana